Publications by authors named "Tasnima Alam Asa"

This study focused on the efficient post-transcriptional incorporation of a modified nucleoside at the end of the poly-A tail of mRNA. The modified mRNA was obtained in high yield and served to enhance protein expression. Utilizing poly-U polymerase, our method successfully enabled a single 2'OMeU residue to be incorporated into mRNA, which unexpectedly provided significant stabilization, even with only a single incorporation, to enhance the resistance of mRNA to degradation by cellular exonuclease.

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In this study, we developed an isothermal fluorometric diagnostic method for DNA virus-generating disorders such as Mpox. Our results showed that the release of a large number of protons during multiplex-LAMP markedly lowered the pH level, which transformed the retinoblastoma (Rb) linear ssDNA into i-motifs. Consequently, thiazole orange (TO; a fluorometric probe sensitive to the i-motif) boosted the signal-on fluorescence because of its ability to bind selectively to i-motifs.

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Article Synopsis
  • A new detection system combining a PK-probe with ligation-transcription-ramified RCA allows for the colorimetric detection of miRNA 25-3P, changing its color from pink to colorless in the presence of pyrophosphate.
  • The system achieves a remarkably low detection limit of 91.4 aM, making it highly sensitive compared to other colorimetric methods.
  • It also demonstrates high specificity due to dual-selective ligation steps, enabling it to differentiate between perfectly matched and mismatched target sequences, suggesting its potential as an effective diagnostic tool for miRNA detection.
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Herein, we introduce a novel assay for multiple-gene recognition by ligation-double transcription mediated fluorometric profiling. We demonstrated the capability of the system to identify potential multi-gene classifiers for diagnostic use by employing a combination of a ligation-double transcription approach with a selective fluorophore probe-RNA hybridization/graphene oxide quenching system. The system is efficient and requires only 45 minutes for total experimentation and offers high sensitivity (369.

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In this paper we present a new method for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), targeting a specific region "N gene." Under isothermal reaction conditions, we integrated ligation (Lig; high selectivity) and recombinase polymerase amplification (RPA; high sensitivity) processes, obtaining a robust method of detection. For point-of-care testing, we incorporated our laboratory-produced pyrophosphate ion (PPi)-sensing probe (PK-probe) for colorimetric analysis of the reaction.

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In this study we developed a very simple and rapid miRNA 21 detection system using a novel quinolinium diethylamino salicylaldehyde (QnDESA) probe for sensing the 22AG hybrid G-quadruplex with a single-step rolling circle amplification (RCA) reaction. We synthesized a circular DNA padlock template containing a sequence complementary to the 22AG hybrid G-quadruplex, used SplintR ligase to ensure perfect hybridization with miRNA 21, applied this circular DNA and phi-29 DNA polymerase for tandem amplification of the 22AG hybrid G-quadruplex sequence, and then probed the product using QnDESA. This combination of RCA-G-quadruplex and QnDESA allowed the rapid (1 h) and simple one-pot detection of miRNA 21 based on a change in fluorescence.

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